Aflatoxins are toxic secondary metabolites produced by fungi Aspergillus Flavus Link and A. Parasiticus Speare, which are classified into B1, B2, G1 and G2 types. The fungi Aspergillus Flavus Link mainly produce B1 and B2 types, whereas the fungi A. Parasiticus produce G1 and G2 types, in addition to B1 and B2 types. Among those types, B1 type is the most vicious carcinogenic substance.
Taking food and Chinese herbal medicines polluted with aflatoxins of high concentration may lead to diseases of hepatotoxicity, teratogenicity or immuno-supression, sometimes leading to deaths. Further, the food poisoning caused by aflatoxins, Aflatoxin-cosis, is a liver disease characterized by vomit, stomachache, spastic, pulmonary edema, coma or store fat in liver, kidney and heart or hydrocephalus, which may result in deaths. It is found, in the African and Asian epidemiological studies, that people in the regions of higher levels of aflatoxins pollution are more susceptible to liver cancer. Further, atlatoxins are a cause why B-type hepatitis virus carriers develop liver cancer.
To avoid endangering human health, the conventional method for suppressing aflatoxins is storing food or Chinese herbal medicines in a fungi-unfriendly environment, such as places of low humidity, whereby the chance for fungi growth is suppressed, and aflatoxins produced during the proliferation and metabolism of fungi become limited. Therefore, the chance of aflatoxin pollution on food become low. We can also remove the aflatoxin pollution by a mechanical means, which is particularly applied to remove the polluted portions of food contraindicated by aflatoxins. Thereby, unpolluted portions of food or Chinese herbal medicines can be kept for future consumptions. Further, the toxicity of aflatoxins can be damaged by alkali-added solvents and reduced to safety level.
However, the storage of food or Chinese herbal medicines in a dry space, though being capable of suppressing fungi growth, will cause management problem if it lasts for a long period of time. Similarly, the mechanical removal of aflatoxins by taking away polluted portions of food cannot guarantee that the remained portions is not polluted by aflatoxins. Especially, it cannot recognize the portions covered by the expansion of the pollution. Finally, the addition of alkali substances into a solvent and then reducing of the toxicity of aflatoxins in food may cause harmful quality changes of the food.
Therefore, the conventional methods of suppressing aflatoxins in food or Chinese herbal medicines have at least the following disadvantages.                1. The incomplete removal by the mechanical means;        2. The effect of chemical substances left during the toxicity reduction of aflatoxin by alkali-added solvents on human health.        